Tank fitting



M w a. my Mg M M CUNNHNGHAM 'mm FITTING Filed July 4, 1945 'RANK FE'EmG Marion Ml. Uunningham, South Bend, Ind.. as-

signor to United States Rubber Company, New York, N. Y., a corporation of New Jersey Application duly d, 1945, Serial No. 603,217 d Claims. (Ci. 28E-38) This invention relates to a tank ntting for providing an opening in a wall of the tank to which may be attached an inlet or an outlet connection, or a closure therefor. The tting is particularly applicable to a tank having iiexible walls which require a flexible iiange reinforced with textile fabric for connecting the fitting to the tank wall, and it is an improvement over the tting disclosed in my prior Patent No. 2, 366,dd2, granted January 2, 1945.

it is the usual practice to reinforce the walls of flexible tanks with one or more layers of a textile fabric which is coated or impregnated with a rubber composition, or rubber like material to render its surfaces impervious tothe liquid contents to be deposited in the nlshed tank. The tting is attached to the walls of the tank by means of a iabric reinforced disc like ring or flange which has been similarly treated to render it impervious to liquids,- and so that it may be bonded to the tank wall. Thetank wall is cut to form an opening therein for the tting and the fabric reinforced flange is also cut to the proper shape. in order to protect the rubber treated fabric from being disintegrated by some liquids which may be contained in the tank, it is necessary to prevent the cut edges of the textile fabric of the tank wall opening and of the tank iitting from coming in contact with the contents of the tank and absorbing the liquid by wick action into the rubber treated fabric. In my prior patent, the cut edge forming the inner periphery of the fabric iiange was protected by a, layer of rubber which covered the entire inner periphery of the fitting and extended over its top and bottom surfaces. In that construction it was necessary to mold the rubber in place which is more expensive and utilizes more rubber than my present ttlng.

In accordance with my present invention a reduction in the weight of materials is effected, and the molded layer of rubber in the prior construction is eliminated in the manufacture of the fitting by sealing the inner periphery of the edges of the fabric ange in a case formed by the metal parts of the ntting.

The present invention has as a further object an improved construction for facilitating the assembly of the metal parts in tight engagement with the treated fabric flange, which eventually forms a part of the tank wall, or in tight engage ment with the margin of an opening in the tank` wall.

The foregoing and other objects of this invention will be more clearly understoodby referringv to the following description and the accompanying drawings, in which:

Fig. i' is a perspective view oi a tank having a fitting embodying this invention applied thereto;

Fig. 2 is a vertical section of the fitting shown in Fig. 1 and having an inlet connection attached thereto;

' Fig. 3 is an enlarged view of a portion of the iitting shown in Fig. 2; and

Fig. 4 is an enlarged cross sectional view of the tank fitting, illustrating its application to a fuel tank having a wall construction adapted t seal bullet holes.

Fig. l discloses a tank lll having a fitting l I embodying this invention connected thereto. The details of the fitting l! and the manner in which it is connected to the wall of the tank I d, is shown in Fig. 2. As illustrated herein the walls of the tank I0 are made of flexible rubberized fabric, and

the iitting II is provided with a flange l2 comprising one or more layers of fabric and rubber which are united to the wall of the tank it, preferably with a vulcanized bond. The liange l2 is clamped between a rigid base ring i3 and a second rigid outer ring it. The base ring i5 is provided with an axially extending internal flange l5, which projects within the central openings, or inner peripheries It, of the flexible connecting iiange I2 and the outer ring it for the purpose of sealing the cut edge of the inner periphery of the flange IZ from the liquid contents of the tank l0.

The base ring I3 is provided with a plurality of projections or domed nuts l 'l which are internally threaded to receive cap screws I8 for securing to thetting I I an element I9, which may be an inlet or an outlet connection, or a cover plate. A gasket 20 having the characteristic of not absorbing the liquidcontents of the tank Ill is interposed between aange 2l on the element I9 and the outer tting ring I4 for the purpose of sealing the connection between the element I9 and the itting.

When the cap screws I8 are tightened, a liquid tight seal is formed between a seat 22 on the end of the axially extending flange I5 andthe gasket 20, so that liquid cannot seep from the .throat 23 of the flange 23 past the seat 22 and down the outer periphery of the flange I5 to the inner periphery of the opening I5 in the fabric reinforced fiange I2, where the cut edges of the textile fabric is not securely protected by a liquid repellent rubber covering. The gasket 20 also forms a seal with the bottom surface of the flange 2| on the element I9, It will be noted by that construction the cooperation between the gasket 20 and the seat 22 further protects the edges oi' th'e textile fabric in the event the joints between the ring I4 and the flange I5 and projections II are not leak proof.

In cases where a heavy tting is undesirable, thebase ring I3and the outer ring Il are made of light metal, such as aluminum, or an aluminum alloy. These lighter metals are not suitable for forming a strong threaded connection. Therefore the internally threaded projections I1 are desirably made of a harder and stronger metal. In such construction the projections Il are preformed with a base I'I', and the base ring I3 is cast around them, whereby they are retained in the ring in the nature of inserts.

The assembly of the ntting I I before it is united to the wall of the tank III will now be described. The nexible flange I2 is made of two layers of material which are cut in the form of concentric discs 24 and 25. 'Ihe disc 24 is made of unvulcanized rubber treated fabric, and is smaller than the unvulcanized rubber collar 25 to which it is adhered. The central opening I6 is formed in' the assembled flange I2 to correspond with the outer diameter of the flange I 5; and other openings are formed therein to correspond with the outer diameter of the projections I'I on the base ring I3. which extends between the rings I3 and I4, is coated with rubber cement. The flange is then assembled on the base ring I3 so that th'e openings formed therein properly match with the flange I5 and the projections I1. The projections I'I are preferably provided with longitudinally or axially extending serratlons. and the outer ring i4 is provided with openings adapted to llt over the serrated projections I1 and around the flange I5 with a pressed fit. The rings are assembled in matching relation and pressed together so that the flexible flange I2 is tightly clamped therebetween. The rubber cement on the nange I2 assists in bonding it to the rings I3 and I4 and in sealing the joints between the ring I4 and the flange I5 and the projections I 1.

The fitting thus assembled is then applied to the opening in the tank wall in the usual manner by vulcanizing it to the rubberized fabric III' of the tank wall. At the same time the rubber of the flange I2 is also vulcanized. The inner rubber layer 25 extends over the outer periphery of the rubberized fabric layer 23 and is vulcanized to the tank wall. The cut fabric outer periphery 25 is thereby protected from exposure to the liquid contents of the tank.

The fitting previously described, and embody- A ing this invention, is also applicable to fueltanks of the type used in military aircraft in which the The flange I2 including the portion walls of the tank are so constructed that punctures produced by bullets are self-sealed. Such an application is illustrated in Fig. 4 where the fabric reinforced flange 28 to be connected to the tank wall is made of a slightly different construction, and its union with the wall is also different, but otherwise the fitting is the same as the one previously described. The flange 28 comprises an intermediate layer 23 of' fabric treated with unvulcanized rubber which is sandwiched between an outside layer oi' fabric 3|! and an inside layer of rubber 3I, the inner periphery of the flange being clamped between a base ring 32 and an outer ring 33.

The layers of the flange 23 are not bonded tojoint between the flange and the tank wall 3l, forming the bullet hole sealing construction. The wall 34 of the tank comprises two layers 35 of a sealant, which may be either an artificial or natural rubber composition and is usually vul- Canized Slightly to prevent the rubber from completely disintegrating in gasoline, but not to a point where it will not swell readily. The outer layer 35 is adhered to a fabric covering 36, preferably of the two ply tire cord type, and it extends allaround the tank wall to give it mechanical strength. The inner layer of the sealant35 is adhered preferably to a. synthetic rubber layer 3l which is chemically resistant to the liquid contents of the tank and is adapted to protect the sealant therefrom. A layer 38 of fabric of the tire cord type is interposed between the layers 35 and is adhered thereto.

Before arranging the layers of material of the tank wall 34 and the flange 28 in the joint as shown in Fig. 4. all of the overlapping surfacesv of the joint layers are coated with a vulcanizable cement. After the layers are firmly adhered together a ring 39 of reinforcing fabric is adhered over the edge of the outer periphery of the outer fabric layer 30 of the flange 2B. After the joint has been assembled it is vulcanized in the usual manner to securely unite the adjaecnt layers. The direct union lbetween the fabric layers of the wall 34 and flange 28 gives the joint mechanical strength.

While the tank tting embodying this invention has been described more or less in detail, it will be understood that changes may be made therein without departing from the scope of the appended claims and the spirit of the invention.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

1. In a tank tting having an opening therein adapted to have an element attached thereto in sealed relation, a base ring having an axially projecting flange extending around its inner periphery, said base ring having internally threaded projections extending from the face of said ring, a member adapted to be secured to a wall of said tank, said member surrounding said flange and having openings tted over said projections, a second ring having openings therein and an inner periphery press fitted, respectively, over said projections and said ange to clamp said member between said rings.

2. In a tank fitting having an opening thereinl having openings into which said projections are gether in the area. outside of the rings 32 and 33 fitted. a second ring having openings therein and an inner periphery press fitted respectively around said projections and said :flange to clamp said flexible member therebetween.

3. In a fuel tank tting having an opening therein adapted to have an element attached thereto in sealed relation, a base ring having an axially projecting flange extending around its inner periphery, said base ring having internally threaded projections extending from and anchored below the face of said ring, a flexible rubber treated fabric member adapted to be secured to the wall of said tank, said flange and projections extending, respectively into openings in said flexible member, a second member having openings therein and an inner periphery press iitted, respectively around said projections and said ange to clamp said member between said rings, a seat on the end of said ange, a. gasket tted over said second ring and said seat, and bolts an; chored in said threaded projections to hold said first ring to clamp said disk therebetween and hold said parts together, said tank wall comprising lo 593,400

outer and inner layers of rubberized textile fabric, said disk having outer and inner layers of rubberized textile fabric placed adjacent to said texv tile layers in said tank wall and vulcanized in situ MARION M. CUNNINGHAM.

REFERENCES CITED The following references are of record in the 5 thereto.

l0 file of this patent:

UNITED STATES PATENTS Number Name Date 2,336,885 Pepersack Dec. 14, 1943 2,370,799 Kelley Mar. 6, 1945 2,391,373 Wickstrum Dec. 18, 1945 FOREIGN PATENTS Number Country Date France Feb. 14, 1925 

